A case of new-onset atrial fibrillation subsequent to activation of neuraxial anesthesia is presented. The development of atrial fibrillation was temporally related to placement and dosing of an epidural catheter, and may have been triggered by a vagal response to dosing of the anesthetic or the resulting treatment with fluid and an adrenergic agent. The literature on the acute preoperative management of atrial fibrillation and the implications of atrial fibrillation for the patient undergoing regional anesthesia are reviewed.